Maarten, yes, to avoid autoscaling use the PlotRange option:
Show[Graphics[img, PlotRange->{0,255}] ]
see Section 2.5 of the documentation (User's Guide) for another example.
Regards, Mariusz
>>> On 2/6/2006 at 3:02 am, in message <ds6vqe$8of$1 at smc.vnet.net>, Maarten
van
der Burgt<maarten.vanderburgt at icos.be> wrote:
> After loading the Digital Image Processing package (<<imageprocessing`)
> The following command generates a 100 x 100 pixel graylevel image with
> gray values (GV) in the range of 50 ot 180.
>
> img =ToGrayLevel[Table[Random[Integer, {50, 180}], {100},{100}]]
>
> The default way to show this image on screen is:
>
> Show[Graphics[img]];
>
>
> But, assuming the complete GV range I am working with is 0-255, I want to
> display the image with 0 as black and 255 as white.
>
> I know this can be done using:
>
> Show[Graphics[Raster[RawImageData[img],{{0,0},{100,100}},{0,255}]],
> AspectRatio->Automatic]
>
> But, compared to the firste Show[...] expression, this is a rather
> cumbersome way of doing this.
>
> Is there a shorter way to display a graylevel images properly scaled
> (0-255). I did not find anything in the Digital Image Processing
> documentation.
>
> Thanks for your help.
>
> Maarten